Strategies for classifying chronic orofacial pain patients.

To communicate, understand, and prescribe treatment, it is essential that some consensually validated criteria be used to describe groups of patients who share a set of relevant attributes. Several classification systems have been developed to described relatively homogeneous subgroups of chronic pain patients. These systems have been based on theoretical perspectives of chronic pain syndromes tied to physical pathology. Alternative systems based on a priori psychological categories or empirically derived classifications also have been proposed. Some of the strengths and weaknesses of deductive and inductive approaches to classification are described, and the advantages of polydiagnostic and multiaxial approaches are described as alternatives to the traditional classification. Research on an empirically derived multiaxial classification for chronic pain is described and related to chronic orofacial pain.